Warnings:
The “type” attribute is unnecessary for JavaScript resources.
The “type” attribute for the “style” element is not needed and should be omitted.
The “banner” role is unnecessary for element “header”.
The “main” role is unnecessary for element “main”.
Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.
Attribute “<br” is not serializable as XML 1.0.
Attribute “helpers"” is not serializable as XML 1.0.
Attribute “unavailable."” is not serializable as XML 1.0.
Attribute “lesson,” is not serializable as XML 1.0.
Attribute “3-minute” is not serializable as XML 1.0.
Attribute “firefighter’s” is not serializable as XML 1.0.
Attribute “scary,” is not serializable as XML 1.0.
Attribute “underneath.<br” is not serializable as XML 1.0.
The first occurrence of ID “yellow” was here.
The first occurrence of ID “app-case-of-the-missing-smoke-alarms” was here.
The first occurrence of ID “video-button-lessons” was here.
Errors:
The element “noscript” must not appear as a descendant of the “noscript” element.
Bad value “button” for attribute “type” on element “a”: Subtype missing.
The “sizes” attribute may be specified only if the “srcset” attribute is also present.
No space between attributes.
Saw “<” when expecting an attribute name. Probable cause: Missing “>” immediately before.
Attribute “<br” not allowed on element “a” at this point.
Self-closing syntax (“/>”) used on a non-void HTML element. Ignoring the slash and treating as a start tag.
Quote “"” in attribute name. Probable cause: Matching quote missing somewhere earlier.
Duplicate attribute “the”.
Attribute “firefighters” not allowed on element “a” at this point.
Attribute “are” not allowed on element “a” at this point.
Attribute “community” not allowed on element “a” at this point.
Attribute “helpers"” not allowed on element “a” at this point.
Attribute “can” not allowed on element “a” at this point.
Attribute “be” not allowed on element “a” at this point.
Attribute “used” not allowed on element “a” at this point.
Attribute “to” not allowed on element “a” at this point.
Attribute “introduce” not allowed on element “a” at this point.
Attribute “the” not allowed on element “a” at this point.
Attribute “lesson” not allowed on element “a” at this point.
Attribute “if” not allowed on element “a” at this point.
Attribute “suggested” not allowed on element “a” at this point.
Attribute “book” not allowed on element “a” at this point.
Bad value “” for attribute “is” on element “a”: Must be non-empty.
Attribute “unavailable."” not allowed on element “a” at this point.
Duplicate attribute “a”.
Duplicate attribute “community”.
“<” in attribute name. Probable cause: “>” missing immediately before.
Attribute “lesson,” not allowed on element “a” at this point.
Attribute “this” not allowed on element “a” at this point.
Attribute “3-minute” not allowed on element “a” at this point.
Attribute “video” not allowed on element “a” at this point.
Attribute “helps” not allowed on element “a” at this point.
Attribute “children” not allowed on element “a” at this point.
Attribute “understand” not allowed on element “a” at this point.
Attribute “that” not allowed on element “a” at this point.
Attribute “while” not allowed on element “a” at this point.
Attribute “a” not allowed on element “a” at this point.
Attribute “firefighter’s” not allowed on element “a” at this point.
Attribute “gear” not allowed on element “a” at this point.
Attribute “might” not allowed on element “a” at this point.
Attribute “look” not allowed on element “a” at this point.
Attribute “and” not allowed on element “a” at this point.
Attribute “sound” not allowed on element “a” at this point.
Attribute “scary,” not allowed on element “a” at this point.
Attribute “there” not allowed on element “a” at this point.
Attribute “helper” not allowed on element “a” at this point.
Attribute “underneath.<br” not allowed on element “a” at this point.
An “img” element must have an “alt” attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images.
Bad value “100%” for attribute “width” on element “img”: Expected a digit but saw “%” instead.
Duplicate ID “yellow”.
Duplicate ID “app-case-of-the-missing-smoke-alarms”.
Attribute “value” not allowed on element “a” at this point.
Duplicate ID “video-button-lessons”.
Too many messages.